Apparatus and method for fitting struts to propeller shafts of boats and the like



June 23, 1959 A. E. KAMMRITZ 2,891,316

APPARATUS AND METHOD FOR FITTING STRUTS TO PROPELLER SHAFTS 0F BOATS ANDTHE LIKE Filed March 21, 1956 Y I 2 Sheets-Sheet 1 IN V EN TOR.fiETHl/FP E h flmvm TZ.. BY &M' Mu'a f] T TOFNEY,

June 23, 1959 A. E. KAMMRITZ 2,891,316 APPARATUS AND METHOD FOR FITTINGSTRUTS TO PROPELLER SHAFTS 0F BOATS AND THE LIKE 2 Sheets-Sheet 2 FiledMarch 21, 1956 INVEN TOR. fl/P THU}? E. Kan/1m T2.

United States METHOD FOR FI'llTING STRUTS SHAFTS OF BOATS AND THEAPPARATUS AND TO PROPELLER LIKE This invention relates to an apparatusfor fitting struts .to propeller shafts of boats and the like. In boatshaving an inboard motor with a propeller shaft extending through thebottom .of the boat, the said shaft is. generally supported by a singleleg strut which includes a bearing, surrounding a portion of the shaft,and a leg extending from said bearing and having a foot by means ofwhich the strut is secured to the bottom of the boat. Such single legstruts have. been found objectionable for the reason that, due to thesingle leg, the bearing is supported only in a vertical direction andlateral movement thereof can occur and cause excessive vibration duringrotation of the propeller shaft.

Such vibration is practically eliminatedby the use of what is known as aV-type strut, i.e., a strut having the bearing and two legs extendingupwardly thereon in the shape of a V and each leg having a foot forsecuring the. strut to the bottom of the boat.

Such v-type struts are usually installed on boats to re place the singleleg struts and have to be made to conform with the bottom of the boatand with the angle of the propeller shaft relatively to said bottom.This usually involves working with compound angles and it has heretoforebeen found extremely diflicult and inconvenient to fit said struts tothe boats because it has been done by the fit and try method which hasresulted in considerable loss of time as well as in spoilage of strutson account of errors.

An object of the present invention, therefore, is to provide a novelapparatus which may be adjusted to conform with the exact, formation ofthe boats bottom and with the disposition of the propeller shaft inrelation to said bottom so that said apparatus may then be used forfitting the strut directly thereto in such a manner that, after thestrut has been shaped to fit the adjusted apparatus, it will accuratelyfit on the boat and shaft without any further shaping or fitting.

A further object is to provide a portion of said device in the formhereinafter called a negative template, which may be adjusted to conformwith the boatsv bottom and shaft, and another portion in the formhereinafter called the positive template that may be adjusted to theconforming negative template and then used in lieu of the actual boatand shaft for accurately fitting the strut thereto before finalinstallation on the boat.

A further object of this invention is to provide an apparatus whereby anegative template may be made directly from the boat wherever it happensto be located, the saidnegative template then transported to a dilferentlocation where the strut can be constructed or'shaped to accuratelyconform therewith, and the said strut then delivered to the location ofthe boat and finally installed without requiring any further fitting.

Further objects and advantages of this invention will be more clearlyunderstood fromthe following descrip tion and-the accompanying drawingsin which:

atent Ci Patented June 23 1959 Fig. 1 is a plan view of the negativetemplate includedin my improved. apparatus.

Fig. 2 is a rear view thereof.

Fig. 3 is a side view thereof with portions of the boats bottom and the.propeller shaft being indicated in dotted lines.

Fig. 4 a side view showing the shaft engaging portion of said templatein a different position.

Fig. 5 is a frontv view showing said portion partly in section on line5- 5.01. Fig. 4.

V Fig. 6 is a side view of an upper portion of said negative templateshowing one of the. members for measuring the. angle of the boatsbottom.

Fig. 7 is a side view of the. positive template that included in saidapparatus; the position of a strut thereon being indicated in dottedlines.

Fig. 8 is a front view of said positive template and strut.

As shown in the drawings, the negative template of said apparatusincludes. a. pair of crossed supporting bars 5 and 6 on which there are.slidably mounted apair of sleeves 7 and 8, respectively, which areadjustably secured on said bars by clamping screws 9 and 10,respectively. The said sleeves have opposed plate-like projections 11and 12 thereon which are parallel to and spaced from each other toreceive. therebetween a stem portion 13 of an elongated. V-shaped member14- which is pivotally mounted between said extensions 11 and 1 2 bymeans of a pivot pin 15 and is. angularly adjustable on said extensionsby a-c1amping screw 16 which. extends through an arcuate slot 21 on saidmember 13. for securing the yoke in clamp A clamping screw 22 isthreaded to. and extends through the said yoke for clamping the member13 to the propeller shaft, as will hereinafter be more fully described.

Adjacent the upper ends of the bars 5 and 6, there are mountedsupporting, brackets 23' and 23-11 which are rigidly secured to theirrespective bars and have extensions 24 and 24-a from which project studs25 and ZS-a, upon, which are rotatably mounted knuckle members 26 and26a that are rotatably adjustable on said studs and clamped thereon inadjusted positions by means of, clamping screws 27 and 27-01. The saidknuckle members have extensions. 28 and 28-a with studs 29. and 29-aprojecting therefrom on which there are mounted rotatably adjustablemeasuring plates 30 and 30-a which are adapted to engage the oppositesides of the boats bottom, indicated at 31, and be adjusted by means ofclamping screws 32 and 32a to conform therewith and thereby provide ameasurement of the angular relation between the opposite sides of saidbot.- tom and; between the said bottom and the propeller shaft when saidnegative template is mounted upon. the propeller shaft indicated at 33,as shown in Fig. 3..

My invention also contemplates the use of a positive template, such asillustrated in Figs. 7 and, 8, which preferably includes a base 35' uponwhich. there is horizontally and rigidly mounted a post 36. A supportingbracket 37. is rotatably adjustable upon said post and may be clamped indifferent positions by means of acl'arnping screw 38'; A pair ofangul'arly disposed supporting bars 39 and 39-42 are mounted upon saidbracket 37 andcarry thereon supporting sleeves 40" and 17 in said stemportion and 40-a which are slidably adjustable on'said bar by means'mounted the plates 46 and 46a that may be. secured in adjustedpositions upon said studs by meansof clamping screws "47 and 47-11.

The bracket 37 has mounted thereon a horizontally disposed shaft 48which projects forwardly of said bracket andcorresponds to the propellershaft of the boat and has a standard shank 748 a so that such shafts ofdifferent diameters, conforming with the diameters of.differentpropeller shafts, may be mounted upon the bracket 37 and secured theretoby the set screw 37-a. A collar 49 is slidably adjustable on said shaftto provide'a stop for locating the strut, as shown in 'Fig. 7,

As indicated in dotted lines in Figs. 7 and 8, a V-type strut which isto be fitted by means of the above described apparatus consistsgenerally of a tubular portion 50, which provides the bearing for thepropeller shaft, a pair of angularly disposed leg portions 51 and 51aand foot portions 52 and 52a upon the ends of said leg portions.

In the use of the above described apparatus, the negative template isfirst adjusted to the exact measurements of the boat which include theangular disposition of the opposite sides of the bottom of the boat withrelation to each other, the angular dispositionof the propeller shaft 32with relation to the said bottom and its distance therefrom; saidadjustment being made by first clamping the device onto the propellershaft, in the position illustrated in Fig. 3, so that the rear end 14-11of said member 14 is located upon the point of the shaft where the rearend of the tubular bearing portion of the strut 50 is to be located;this being generallyat a point forwardly of the hub of the propellerthat is to be mounted on the said shaft.

When the negative template has thus been secured to the propeller shaft,the bars 5 and 6 are adjusted about the pivot point 15 so that they willbe substantially vertical and the said bars are then slid in theirrespective sleeves 7 and 8 and the plates and 3la are adjusted on saidbars into compound angles to bring them into proper contact with theopposite sides of the boats bottom at the areas that are to be engagedby the foot portions 51 and 51-11 of the strut. The said bars and platesare then clamped in adjusted position by means of the clamping screws 9,1t), 16, 27 and 27-a, and 33 and 33a and the entire negative template isremoved from the boat by loosening the clamping screw 22.

The said negative template, having been so adjusted directly upon theboat, may then be transported to another location, which may be distant,where there is suitable equipment for fitting the V-type struts bymachining them or forming certain portions thereof to the requireddimensions and where there is present the positive template illustratedin Figs. 7 and 8. The positive template is then first adjusted toconform with the adjusted negative template by mounting said negativetemplate upon the shaft 48, with the member 14 clamped onto said shaftso that the rear end 14a thereof will be located at a suitable locatingmark on said shaft, such as the line 53. If desired, this locating markmay be designated by the free end of the said shaft-48.

After the said positive template has thus been secured to the negativetemplate with the rear end of the member 14 in line with the designatedlocating mark on the shaft 48, the plates 46 and 46-a are adjusted toconform with the disposition of the plates 30 and 30-a of the negativetemplate by adjusting the said template plates to flatly contact theplates 30 and 30-11 and then securing them in adjusted positions bytightening the clamping screws 44, 44a, 47 and 47-a. When the saidpositive template has been adjusted, as just' described above, the stopcollar 49 is placed upon the shaft 48 and the tubular portion 50 of thestrut is then mounted upon said shaft, as shown in Figs. 7 and 8, andlocated with its rear end at the locating mark 53. The stop collar 49 isthen moved rearwardly against the opposite end of the said tubularportion and secured to the shaft 48 so as to provide a locating stop forthe strut. The said strut is then fitted so that the foot portions 52and 52-a thereof will properly engage the surfaces of the plates 46 and4a which correspond to the bottom of the boat. The said strut may bemachined while on the template, or removed therefrom and then returnedfor fitting. The template may also be rotated upon the post 36 toposition the strut for machining operations such as drilling or planing.

When the strut has been fitted to the positive template, it is simplyremoved by pulling it ofi the shaft 48 and it will then be in shape toaccurately fit the boat and may be transported to the location of theboat for final installation.

I claim:

1. An apparatus for fitting a V-type strut to the propeller shaft andbottom of a boat, said apparatus including a negative template having anelongated V-shaped supporting member adapted to be mounted on saidpropeller shaft and, when so mounted, having its axis parallel to theaxis of the shaft, a clamping member for clamping said supporting memberto said shaft, the said supporting member having a stem portion, a pairof bar supporting brackets pivotally mounted upon opposite sides of saidstem for angular adjustment thereon about an axis transverse to the axisof said supporting member, means for clamping said brackets in adjustedpositions on said stern, a pair of supporting bars axially slidable insaid brackets with their axes crossing under said supporting member andtheir upper ends disposed at oppositesides of the supporting member,means for clamping said bars in different axial positions on thebrackets, a pair of plate supporting brackets mounted adjacent the upperends of said bars, a pair of opposed studs projecting from said platesupporting brackets and disposed horizontally on parallel axestransverse to the axis of the supporting member, knuckle membersrotatably mounted upon said studs, a pair of plate supporting studsprojecting from said knuckle members on axes parallel to the axis of thesupporting member, a pair of plate-like members rotatably mounted uponsaid supporting studs and adjustable upon said bars to compound anglesto conform with surfaces of opposite sides'of said bottom of the boat,means for securing said plate-like members in adjusted positions uponthe knuckle members, and means for securing the knuckle members inadjusted positions upon plate supporting brackets.

2. An apparatus for fitting a strut to a propeller shaft and theopposite sides of the bottom of a boat including a negative templatehaving a supporting member adapted to receive said shaft, clamping meansfor detachably clamping said supporting member to the shaft, the saidsupporting member having a stern portion depending therefrom, opposedbrackets extending from opposite sides of said stem portion andpivotally mounted thereon for angular adjustment relatively to saidsupporting member, each of said brackets having an angularly disposedsleeve, a pair of supporting bars slidably mounted in said sleeves withtheir upper portions ina V formation 7 wherein said upper portions aredisposed at the opposite sides of the supporting member and projectabove said member and the axes of said supporting 'bars intersect underthe supporting member, means for clamping the said supporting bars inadjusted positions in the said sleeves, a pair of plate supportingbrackets mounted adjacent the upper ends of said supporting bars,'aprojection on each of said plate supporting brackets, .a stud rigidlysecured to each of'said projections and ex References Cited in the fileof this patent UNITED STATES PATENTS Fell Feb. 21, 1905 Hunt Dec. 20,1910 Maxwell May 6, 1919 Murphy Feb. 1, 1921 Rice Jan. 8, 1946 PetersonDec. 16, 1952 Laux Jan. 24, 1956

